SEKOLAH MENENGAH KEBANGSAAN IBRAHIM

B I O L O G Y

ENDANGERED ECOSYSTEM

NAME: ADIB AMSYAR B. ILIAS

CLASS: 4 SN 1

I/C NO: 950928-02-6347

CONTENTSHuman Activities That Endanger an Ecosystem

Agriculture

Open Burning

Industrialization

Urbanization

Deforestation

Effects of Human Activities

Pollution

Greenhouse Effect

Thinning Ozone Layer

Steps to Maintain a Balanced Ecosystem

INTRODUCTIONEndangered Ecosystem | 2

The story of the ecosystem on our planet has never been more crucial and relevant than

it is today. In an era of climate change, desertification, sea level rise, acid rain, greenhouse

effect, thinning ozone layer and widespread pollution, ecosystem quality is becoming more

critical by the minute. The global forces of extraction and expansion are jeopardizing the very

substance that supports life on our planet.

There is great truth to the adage that we are all downstream from one another. The

midwestern United States is downstream from the coal-fired power plants of China. The rising

tides inundating the Sundarban Islands of India are downstream from the carbon emissions of

billions of cars around the world. And we are all literally downstream from the melting of the

polar ice caps. How we manage our water resources has implications for many of the critical

issues we face—from women as primary water gatherers, subsistence farming, and the health

and balance of wildlife systems, to water refugees, the health of children, and the spreading of

disease. Unfortunately, these connections are not well understood by the general public, whose

choices as individuals and as a collective can contribute to either the degradation or the

conservation of our water.

Environment is defined as the surroundings in which the organism lives. The

environment may be the physical environment, the chemical environment or the biological

environment. Thus, the environment has two components - abiotic and biotic.

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HUMAN ACTIVITIES THAT AFFECTS THE ECOSYSTEM

Human activities often affect whole ecosystems. With great advancements in the

medical fields, modern farming techniques and better infrastructure, the world’s population

has grown to over 6 billion today.

Conflicts, therefore, arise between the need to meet the immediate human demands in

the short term and need to protect and conserve ecosystems from long-term damage.

Agriculture

Open Burning

Industrialization

Urbanization

Deforestation

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AGRICULTURE

Agriculture is the production of food and goods through farming and forestry.

Agriculture was the key development that led to the rise of human civilization, with the

husbandry of domesticated animals and plants creating food surpluses that enabled the

development of more densely populated and stratified societies. The study of agriculture is

known as agricultural science.

Agriculture encompasses a wide variety of specialties and techniques, including ways to

expand the lands suitable for plant raising, by digging water-channels and other forms of

irrigation. Cultivation of crops on arable land and the pastoral herding of livestock on

rangeland remain at the foundation of agriculture. In the past century there has been

increasing concern to identify and quantify various forms of agriculture. In the developed

world the range usually extends between sustainable agriculture (e.g. permaculture or

organic agriculture) and intensive farming (e.g. industrial agriculture).

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Modern agronomy, plant breeding, pesticides and fertilizers, and technological

improvements have sharply increased yields from cultivation, and at the same time have

caused widespread ecological damage and negative human health effects. Selective

breeding and modern practices in animal husbandry such as intensive pig farming (and

similar practices applied to the chicken) have similarly increased the output of meat, but

have raised concerns about animal cruelty and the health effects of the antibiotics, growth

hormones, and other chemicals commonly used in industrial meat production.

The major agricultural products can be broadly grouped into foods, fibers, fuels, and raw

materials. In the 2000s, plants have been used to grow biofuels, biopharmaceuticals,

bioplastics, and pharmaceuticals. Specific foods include cereals, vegetables, fruits, and

meat. Fibers include cotton, wool, hemp, silk and flax. Raw materials include lumber and

bamboo. Other useful materials are produced by plants, such as resins. Biofuels include

methane from biomass, ethanol, and biodiesel. Cut flowers, nursery plants, tropical fish

and birds for the pet trade are some of the ornamental products.

In 2007, about one third of the world's workers were employed in agriculture. The

services sector has overtaken agriculture as the economic sector employing the most

people worldwide. Despite the size of its workforce, agricultural production accounts for

less than five percent of the gross world product (an aggregate of all gross domestic

products).

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OPEN BURNING

Open burning is defined as "the burning of any matter in such a manner that products of

combustion resulting from the burning are emitted directly into the ambient (surrounding

outside) air without passing through an adequate stack, duct or chimney." Generally, anytime

you light a fire outdoors, you are open burning.

No person may conduct, cause or permit the conduct of a salvage operation by open

burning, and the burning of refuse and other combustible material by open burning is

generally restricted. However, there are some categories of permissible open burning; some

of these are as follows:

Fires for the instruction and training of firefighting personnel.

Fires set for the elimination of a fire hazard.

Fires set for the removal of dangerous or hazardous material.

Campfires and other fires for the outdoor preparation of food.

Agricultural crop burning.

Land clearing and right-of-way maintenance.

No burning of trade waste or materials that generate hazardous air pollutants such as

rubber products (tires), tarpaper, asphalt shingles, plastics or treated wood products will be

approved. Alternatives to burning must be investigated and the request to burn must be

justified fully. Cost of alternative disposal is not sufficient justification by itself.

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Regardless of whether or not the burning is permissible under the rules or whether a

variance to open burn has been issued, all open burning must comply with all of the conditions

contained in Subsection 33-15-04.2. Some of these conditions are as follows:

No public nuisance is or will be created.

No occupied building may be impacted by air contaminants from the burning.

No traffic hazards can be created.

The burning must be attended and supervised at all times.

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INDUSTRIALISATION

Industrialisation is the process of social and economic change whereby a human group

is transformed from a pre-industrial society into an industrial one. It is a part of a wider

modernisation process, where social change and economic development are closely related

with technological innovation, particularly with the development of large-scale energy and

metallurgy production. It is the extensive organization of an economy for the purpose of

manufacturing.

Industrialisation also introduces a form of philosophical change where people obtain a

different attitude towards their perception of nature, and a sociological process of ubiquitous

rationalisation. There is considerable literature on the factors facilitating industrial

modernisation and enterprise development. Key positive factors identified by researchers have

ranged from favourable political-legal environments for industry and commerce, through

abundant natural resources of various kinds, to plentiful supplies of relatively low-cost, skilled

and adaptable labour.

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One survey of countries in Africa, Asia, the Middle East, and Latin America and the

Caribbean in the late 20th century found that high levels of structural differentiation, functional

specialisation, and autonomy of economic systems from government were likely to contribute

greatly to industrial-commercial growth and prosperity. Amongst other things, relatively open

trading systems with zero or low duties on goods imports tended to stimulate industrial cost-

efficiency and innovation across the board. Free and flexible labour and other markets also

helped raise general business-economic performance levels, as did rapid popular learning

capabilities.

Positive work ethics in populations at large combined with skills in quickly utilising new

technologies and scientific discoveries were likely to boost production and income levels – and

as the latter rose, markets for consumer goods and services of all kinds tended to expand and

provide a further stimulus to industrial investment and economic growth. By the end of the

century, East Asia was one of the most economically successful regions of the world – with free

market countries such as Hong Kong being widely seen as models for other, less developed

countries around the world to emulate. The first country to industrialize was Great Britain

during the Industrial Revolution.

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URBANIZATION

Urbanization is the physical growth of urban areas as a result of global change. Urbanization

is also defined by the United Nations as movement of people from rural to urban areas with

population growth equating to urban migration. The United Nations projected that half of the

world's population would live in urban areas at the end of 2008. Urbanization is closely linked

to modernization, industrialization, and the sociological process of rationalization.

As more and more people leave villages and farms to live in cities, urban growth increases.

The rapid growth of cities like Chicago in the late 19th century and Shanghai a century later can

be attributed largely to people from rural communities migrating there. This kind of growth is

especially commonplace in developing countries.

The rapid urbanization of the world’s population over the twentieth century is described in

the 2005 Revision of the UN World Urbanization Prospects report. The global proportion of

urban population rose dramatically from 13% (220 million) in 1900, to 29% (732 million) in

1950, to 49% (3.2 billion) in 2005. The same report projected that the figure is likely to rise to

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60% (4.9 billion) by 2030. However, French economist Philippe Becquerel, writing in THE

FUTURIST magazine, has calculated that "the proportion of the world population living in cities

and towns in the year 2030 would be roughly 50%, substantially less than the 60% forecast by

the United Nations (UN), because the messiness of rapid urbanization is unsustainable. Both

Becquerel and the UN see more people flocking to cities, but Becquerel sees many of them

likely to leave upon discovering that there’s no work for them and no place to live."

Urbanization is not always attributed to high density. In Manila, the cost of living has forced

residents to live in low quality slums and shanty towns.

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DEFORESTATION

Deforestation is the clearance of naturally occurring forests by the processes of people's

logging and/or burning of trees in a forested area.

Environmental issues effect every life on this planet from the smallest parasite to the human

race. The reason for this is simple. A single disruption in the Earth’s delicate balance can mean

certain destruction of the very place that cradles the lives of many species. What is not so

simple is finding alternatives to the now dangerous and confronting acts of planet degradation

that have been afflicted on the planet over recent years. One such issue that requires

consideration is deforestation. Trees have been or are being cut down at increasingly high

rates. If this is not stopped many unfavorable side effects could result.

Deforestation occurs because of many reasons: trees or derived charcoal are used as or sold

for fuel or a commodity to be used by humans, while cleared land is used by humans as pasture

for livestock, plantations of commodities, and settlements. People's removal of trees without

sufficient reforestation has resulted in damage to habitat, biodiversity loss and aridity. It has

adverse impacts on bio sequestration of atmospheric carbon dioxide. Deforested regions

typically incur significant adverse soil erosion and frequently degrade into wasteland.

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Disregard or ignorance of intrinsic value, lack of ascribed value, lax forest management and

deficient environmental law are some of the factors that allow deforestation to occur on a large

scale. In many countries, deforestation is an ongoing issue that is causing extinction, changes to

climatic conditions, desertification, and displacement of indigenous people. Logging was the

major cause of global deforestation.

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EFFECTS OF HUMAN ACTIVITIES

The Human Activities all over the world made by mankind had gave many impact to the

mother nature. The negative effects of hasty, unplanned development and the

mismanagement of the ecosystems result in various environmental problems such as air

and water pollution, the greenhouse effect, global warming, and the depletion of natural

resources.These problems bring about negative effects that increasingly threaten the

economic resources health and survival of ecosystems.Some human activities that have

undesirable effects in the environment.

Many of the problems related to the environment are the results of human activities

and human interference with the ecosystems.

Pollution

Greenhouse Effect

Thinning Ozone Layer

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POLLUTION

Pollution is the introduction of contaminants into an environment that causes instability,

disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms.

Pollution can take the form of chemical substances, or energy, such as noise, heat, or light.

Pollutants, the elements of pollution, can be foreign substances or energies, or naturally

occurring; when naturally occurring, they are considered contaminants when they exceed

natural levels. Pollution is often classed as point source or nonpoint source pollution.

Pollution comes from both natural and manmade sources. Pollution can also be the

consequence of a natural disaster. For example, hurricanes often involve water contamination

from sewage, and petrochemical spills from ruptured boats or automobiles. Larger scale and

environmental damage is not uncommon when coastal oil rigs or refineries are involved. Some

sources of pollution, such as nuclear power plants or oil tankers, can produce widespread and

potentially hazardous releases when accidents occur.

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Adverse air quality can kill many organisms including humans. Ozone pollution can cause

respiratory disease, cardiovascular disease, throat inflammation, chest pain, and congestion.

Water pollution causes approximately 14,000 deaths per day, mostly due to contamination of

drinking water by untreated sewage in developing countries. An estimated 700 million Indians

have no access to a proper toilet, and 1,000 Indian children die of diarrhoeal sickness every day.

Nearly 500 million Chinese lack access to safe drinking water. 656,000 people die prematurely

each year in China because of air pollution. In India, air pollution is believed to cause 527,700

fatalities a year. Studies have estimated that the number of people killed annually in the US

could be over 50,000.

Oil spills can cause skin irritations and rashes. Noise pollution induces hearing loss, high blood

pressure, stress, and sleep disturbance. Mercury has been linked to developmental deficits in

children and neurologic symptoms. Older people are majorly exposed to diseases induced by air

pollution. Those with heart or lung disorders are under additional risk. Children and infants are

also at serious risk. Lead and other heavy metals have been shown to cause neurological

problems. Chemical and radioactive substances can cause cancer and as well as birth defects.

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GREENHOUSE EFFECT

The greenhouse effect is the heating of the surface of a planet or moon due to the presence

of an atmosphere containing gases that absorb and emit infrared radiation. Thus, greenhouse

gases trap heat within the surface-troposphere system. This mechanism is fundamentally

different from that of an actual greenhouse, which works by isolating warm air inside the

structure so that heat is not lost by convection. The greenhouse effect was discovered by

Joseph Fourier in 1824, first reliably experimented on by John Tyndall in 1858, and first

reported quantitatively by Svante Arrhenius in 1896.

The black body temperature of the Earth is 5.5 °C. Since the Earth's surface reflects about 28%

of incoming sunlight, the planet's mean temperature would be far lower, about -18 or -19 °C.

Along with the added contribution of the greenhouse effect, it is instead much higher, roughly

14 °C. Global warming, a recent warming of the Earth's surface and lower atmosphere, is

believed to be the result of an ‘enhanced greenhouse effect’ mostly due to human-produced

increases in atmospheric greenhouse gases. This human induced part is referred to as

anthropogenic global warming (AGW).

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The Earth receives energy from the Sun mostly in the form of visible light and nearby

wavelengths. About 50% of the sun's energy is absorbed at the Earth's surface. Like all bodies

with a temperature above absolute zero the Earth's surface radiates energy in the infrared

range. Greenhouse gases in the atmosphere absorb most of the infrared radiation emitted by

the surface and pass the absorbed heat to other atmospheric gases through molecular

collisions. The greenhouse gases also radiate in the infrared range. Radiation is emitted both

upward, with part escaping to space, and downward toward Earth's surface. The surface and

lower atmosphere are warmed by the part of the energy that is radiated downward, making

our life on earth possible.

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THINNING OZONE LAYER

The distribution of ozone in ionosphere, mesosphere and stratosphere is being depleted. The

concentration of ozone is gradually reducing. As the content of ozone is highest in ionosphere

and the air itself being very thin, the depletion is negligible in ionosphere. But in mesosphere

and stratosphere the air is thicker and ozone content is less. The depletion of ozone is of higher

order in these layers. The so called hole in ozone layers simply means that above some

continents (specifically Antarctica, Asia and parts of South America) the mesosphere and

stratosphere have lost their original level of ozone content.

The depletion of ozone layer is a global phenomena both in terms of cause and effect. The

geographical limits of countries are not barriers to either dispersal of gases in layers of

atmosphere or depletion of gases. The causes for depletion may arise in any country. The

effects (in terms of depletion) may arise in any other country. The effects (in terms of ozone

depletion) need not be exactly above the country causing the depletion.

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It is now established that chloroflouro carbon (CFC) chemicals evolved from various

refrigerants, coolants and propellants are the primary reasons for depletion of ozone. CFC are a

group of chlorine bearing gases of low specific gravity. They rise to stratosphere and

mesosphere. Due to ionising solar radiation in these layers, (which is the primary reason for

production of ozone) fresh chlorine gas is produced from CFCs. This nascent chlorine gas has

the capacity to react with ozone and bring down the level of ozone substantially.

The concept of ozone depletion is new. But study of international ozone trendis being made

since 1988, when international ozone commission was established. Extensive ozone assessment

facilities were established under International Middle Atmospheric Programme (IMAP) in India

to study ozone along with number of other green house gases.

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STEPS TO MAINTAIN A BALANCED ECOSYSTEM

The Human Activities all over the world made by mankind had gave many impact to the

mother nature. The negative effects of hasty, unplanned development and the mismanagement

of the ecosystems result in various environmental problems such as air and water pollution, the

greenhouse effect, global warming, and the depletion of natural resources. These problems

bring about negative effects that increasingly threaten the economic resources health and

survival.

1. The need of development and the effects of an increasing population on the ecosystem: Population of the world always increase, so do their needs The needs for more food supplies, water, home has led to development These development involves deforestation, the building more dams, and production of

more domestic and industrial waste The unmanaged and unplanned development leads to a pollution of environment To reduces the negative effects of developments, human must have efforts to manage

the environment properly

2. The importance of proper management of development activities Way to balance the needs for resources with the needs to conserve the natural

resources To make a sustainable development without jeopardizing or depleting the natural

resources Ensure that short-term gains be balance with the long-term effects on the environment To exploit natural resources in a sustainable way, so these resources can be replenish

and renewed for future generations to continue to use them To minimize the negative effects of development towards the environment

3. Measures taken in the management of development activities Implementations of laws Uses of technology Education on the management of resources Preservation and conservation of soil The practice of biological control The use of renewable energy The efficient use of technology

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4. Implimentations of laws Many laws and regulations are designed to control pollution which affects the quality of

lands, air and water. Examples of the acts:

o The Environment Quality Act, 1974, 1989o Motor Vehicle Noise Regulations, 1987o Scheduled Wastes Treatment and Disposal Facilities Regulations, 1989o Clean Air Regulations, Amendment 2000o The National Forestry Act, 1984o The Pesticides Act, 1974o The Fisheries Act, 1985o The Protection of Wildlife Act, 1972

5. Uses of technology Install catalytic converters in vehicle to clean un exhaust emissions and convert harmful

gases released to less harmful gases Use unleaded petrol to reduce the emissions of leads into environment Treat sewage in sewage treatment plants before it’s discharged into the environment Use microorganisms to clean up the environment Develop hydrogen-based fuel-cell vehicle to reduce the burning of fossil fuel

6. Education on the management of resources The public must be educated on the concept of the 4R:

o RECYCLE means collecting segregating waste according to the types of materials and turning this waste into new products

o REUSE means use things such as old plastics containers and bottles again instead of throwing them away

o REDUCE means cutting down on the use of materials which are non-biodegradable

o RENEW means to use materials such as bottles and plastic containers after they are cleaned

7. Recycling is important because: Fewer landfills will be needed to dispose of rubbish It cuts down the use of resources, for example fewer trees will be cut down to make

paper and furniture It saves energy, for example less energy is needed to melt down scrap metal and use it

again than to extract it from the ore

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8. Preservation and conservation Preservations involves efforts to protect an ecosystem Conservations involves efforts to return an affected ecosystem to its natural equilibrium

and keep them good The efforts of conservations includes:

o Preservations of soilo Preservations of watero Preservations of flora and fauna of the foresto Preservations of mangrove swamps

Preservations of soils Make a sustainable agricultural development effectively Good farming technique will prevent erosion and soil

depletion Good agricultural practices includes:

o Crop rotation o Contour farmingo Controlled grazingo Planting cover cropso The appropriate use of fertilizerso Effective drainage and irrigations

Preservations of water Clean water is precious resource and commodity Such as, water sources and water catchment areas must

be preserved Rivers must not be regarded as dumping sites for domestic

and toxic wastes which can pollutes the water The use of nitrates and phosphates in agriculture must be

controlled to prevent run-offs into rivers and ponds

Preservations of flora and fauna of Rainforest Biologists have estimated that Malaysian rainforest

contain more than 50% of the world’s plant and 15 000 of them has not studied yet

If deforestation proceed faster than afforestation, many of these species could become extinct before they can be documented

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Important of forest:o As a diverse storehouse of plant and animal

species which can provide useful and medicine for mankind

o Play an important role in the regulation of microclimate and the concentration of atmospheric carbon dioxide

o Sites for research and education

a) Preservation And Conservation Of Soil, Water, The Flora And Fauna Of Forests, And Mangrove Swamps 

1. The management of natural resources in an ecosystem involves preservation and conservation.

2. Preservation involves efforts to protect an ecosystem so that natural resources are utilised in a sustainable manner and that the equilibrium of the ecosystem is maintained.

3. Conservation involves efforts to return an affected ecosystem to its natural equilibrium.4. Sustainable agricultural development is the effective use and preservation of soil to

ensure continuous agricultural production.a. Good farming techniques will prevent erosion and soil depletion.b. Good agricultural practices include

o Crop rotationo Contour farmingo Controlled grazingo Planting cover cropso The appropriate use of fertiliserso Effective drainage and irrigation

5. Clean water is a precious resource and commodity. As such, water sources and water catchments areas must be preserved.

a. Rivers must not be regarded as dumping sites for domestic and toxic wastes which can pollute the water.

b. The use of nitrates and phosphates in agriculture must be controlled to prevent run-offs into rivers and ponds.

6. The Malaysian rainforests, for example, contain more than 50% of the world’s plant and animal species. Biologists have estimated that Malaysia has more than 15 000 plant species which have yet to be studied.

7. If deforestation proceeds faster than a forestation (conservation of forest areas), many of these species could become extinct before they can be documented.

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8. Therefore, the sustainable use of forests is important to strike a balance between continuing harvesting of forests products, and at the same time maintaining the environmental services of forests.

9. There are many reasons why forests must be conserved and protected. Forests are a diverse storehouse of plant and animal species which can provide useful and medicinal products for mankind. These include fruit trees, ornamental plants, medicinal plants, essential oils, rattan, resin, gum, and tannin. Examples of plants with medicinal value are quinine, which is used to treat malaria, and curare which is used as a muscle relaxant in surgical operations.

10. Rainforests play an important role in the regulation of microclimate and the concentration of atmospheric carbon dioxide.

11. Below are some sustainable and planned forest projects.a. Establishment of a level of selective harvesting. This means only mature trees are

removed.b. Reforestation or large-scale replanting of trees. Replanting programmes ensure

that forests where logging activities have been carried out are not damaged and that the forests continue to be productive and are able to support the diversity of lives.

c. Implementation of restoration programmes to restore damaged habitats so that natural resources and wildlife can be preserved.

d. Establishment of forest reserves to prevent the destruction of existing forests and to maintain the equilibrium of the ecosystem so that the quality of the environment is preserved. This ensures that the diverse flora and fauna do not face the threat of extinction and can continue to survive in their natural habitats. Forest reserves also ensure that the genetic material of animal and plant species will not be lost.

e. Greater productivity form existing agricultural lands will reduce the pressure to convert more forests for agricultural purposes. In this way, farming and harvesting of timber can still be carried out and biodiversity can be protected at the same time.

12. Mangrove swamps are a rich source of biodiversity. Mangrove trees are used as fuel, building materials and pilings. Mangrove swamps provide food, nesting and nursery areas for many animals. The dead leaves and twigs in the water encourage the growth of microorganisms that provide food for young marine organisms.

a. Mangrove swamps play an important role in flood control, nutrient retention, sediment control, and the prevention of coastal erosion. They also act as a barrier against rising sea levels.

b. When an area of a mangrove swamp forest is cleared for aquaculture and development, many plant and animal species are threatened to the point of extinction.

c. Industrial waste pollution also contributes to the threat of extinction.d. Hence, mangrove swamps found along the coastlines must be protected,

preserved and conserved.

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   b) The Practic of Biological Control  

1. Biological control is the use of natural predators to control the population of pest species.

2. Some examples of biological control are :a. The use Khaki chambel (a species of ducks or itik telur) to control the population

of gold snails (siput gondang emas) which feed on paddy stalks.b. The use of caterpillars of the species Cactoblastis cactorum to control the prickly

pear cactus which spreads quickly and invades farming lands.c. The use if the hoverfly larvae to control aphids which feed on crop plants.d. The use of owls to control the population of rats in palm plantation.

3. Biological control is better than using chemical control which involves the use if pesticides. This is because :

a. The use of pesticides is indiscriminate and sometimes harmless organisms as well as the pest species are killed.

b. The effects of pesticides can be persistent and remain in the environment for long periods.

c. The concentration of pesticides is amplified as they pass through food chains (biomagnifications). As a result, high concentrations of pesticides may accumulate in the tissues of final consumers. These pesticides can be toxic and affect the metabolism of the organisms.

d. Pests develop resistance. Hence a larger the amount of pesticides may now be required to produce a similar effect.

e. The cost of using pesticides is high.f. The extensive use of pesticides pollutes the environment.

 c) THE USE OF RENEWABLE ENERGY  

1. Fossil fuels are a non-renewable energy source. Hence, there is a need to look for alternative sources of energy.

2. Renewable energy is energy flow that occurs naturally in the environment and can be harnessed for the benefit of humans.

3. Renewable energy is inexhaustible and does not pollute the environment.4. Examples of renewable energy are :

o Solar energy – which can be converted into electricity and used in heating.o Wind energy – which is used to operate windmills to pump water for the irrigation of crops.o Flowing water – which is used to generate hydroelectric power.o Wave energy – the upward and downward motion of waves is harnessed to generate energy.o Geothermal energy

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o Biomass energy – which is produced when decomposing organic matter, releases a gas consisting of 50% methane. This biogas released can be collected and used as fuel for various purposes such as heating or generating electricity.o Gasohol – is the conversion of energy in biomass. The fermentation of sugar by yeast converts the energy in biomass into ethanol which can be used as fuel. An example of this fuel is gasohol which consists of 80% to 90% unleaded petroleum spirit with 10% to 20% ethanol. Gasohol can be used as fuel in motor vehicles. Plant materials which can be used in the process of fermentation by yeast to produce gasohol are sugar cane, sugar beet and maize.o Palm oil fuel. Palm oil can be converted into methyl ester which is used as fuel. Biodiesel from crude palm oil is an environment friendly alternative to petroleum diesel. Biodiesel can meet approximately 17% of the country’s energy requirements and thereby reduce the country’s dependence on petroleum.

 

d) THE EFFICIENT USE OF ENERGY

1. Reduce the burning of coal, petroleum and other fossil fuels.2. Substitute natural gas for coal at power plants.3. Improve fuel efficiency in vehicles-use cars that run on energy-efficient engines.4. Use a cleaner fuel by reducing the content of sulphur in diesel and switching to gas.5. Improve energy efficiency in factories.6. Use more hybrid cars which combine electric and gasoline engines.

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